Clutch control mechanism



' INVENTOR. Eavm E. FEATHER BY 2 SHEETSSHEE'I 1 ATTORNEY E. E. PRATHER CLUTCH CONTROL MECHANISM June 24, 1952 Flled Sept 30, 1948 June 24, 1952 PRATHER 2,601,626

CLUTCH CONTROL MECHANISM Filed Sept. 30, 1948 2 SHEETSSHEE'I 2 IN VEN TOR. E DWIN E PEA THER ATTORNEY Patented June 24, 1952 OFF I I 2,601,626

CLUICHiCONTROL 1VI E(3H-Al IISM- Edwin-1E; Prathen South Bend; Ind.) assignor'to BenflixAviatiomCnrporation, South'Bend, Ind aacomoratiomofi Delaware Applicationfieptemb'en 30, 1948, Serial No;- 52,087

4:;Glaims'.

This invention relates in general? to: power means for operating" the friction clutch: of an automotive vehicle and in partieul'anto -a=cli1tch: operating pressure difierential operated" power engineof the'vehicle;

Gh flfi' ilie p c 1 2 11 biectsof my invention isto provide a clutch -control -meehanism including" a pressure diiferent'ial operated motor 'controlledsure balanced follow upavalve whiehis operativein=-accordancew-ith thespeed ofitli engine:

Another" obj ect' of" my invention-- 15 to provide: in the power plant of am automotive vehicle ineluding" a friction clutch; a changespeed" trans mission, and an accelerator: a-vacuumaoperated clutch control I mechani'smcomprising a single acting motor; said motonpeing controlledin part by apressure b'alanced -three+wawvalve whiclr is 2e used in the powerplant of anautomotivevehicle, said mechanism including alpressure differential operatedzmoton controlled-by a valve mechanism which is automatically operativetoxeffecta clutch means controlled" inpart' liy anoperationof the" 6; plate loading. operation of the clutch controlmechaniSmLthe'Vdegreeof-loading being dependent upon factors including: the degree of gaseous pressure! within the intake manifold of theien gine of the. vehicle andithe speed: of said engine; by-valVe-mechanisms includinga three=waypresthe: mechanismxbei'n'g automatically operativeto quickly: and i substantially increase the-loading of the: clutch, plates :when the: engine speed is suddenly increased:

Yet anothervobject'. of my. invention isto pro-- vide powermeans for operating the friction clutch of-an automotive-vehicle said power means-'- including: a. single acting pressure difierentlal operated motor: controlled by a power operated three-way valve having fluid transmitting con-- actuated 'by means inclndinga'apressure diiferen- -1 nectionswith the atmosphere, asourceof vanuum,

tial operated motorthe operation" of the valve being also-controlled inpart byanother pressuredifferential operatetrmotor: I

Yet another object of my invention is to pro' vide-power'means for operating the frietionclutch of an automotive vehiole said- -powenmeans-=sewing; to effect two' stages of clutch engaging move merit of the driven element of the ol'utclras itmoves into-engagement with thedriving element I of the clutch said two stage operation: of the gfy'i-hicle" said va'lvemechanism including a th p rt-three way valve two of the parts ofthe 1at clutch driven elementbeing efiectedby arthrot'tl'e' opening movement of the' acceierawr-and by enginespeed controlled means:-

Yet another object of? my invention is-w provide; inthe--power"plant*of amautomotive vehioie including a friction clutch; amaccelratbr; anda" tliree-speeds= forward andreversa transmission; power means for operating the Glut Ch" including apressure difieren ti'al -operated motoroperatively connected tothe" clutch; valve means;- for" corntrolling the operation of said motor 'incliiding a three-way valve-controlled by:a veliicle speed' responsivegovernor; the ac'celerator and tlie changespeed transmission, and' furtherincludingl'a: three=- way bleed valve controlled liy'theaccelerator'andf 5s a plurality-- of" pressure difi'erenti'al operated motors; saidpower means beingope-rative to disengage the clutch by=therelease of the' aoceleraton when the transmissioniszestalilished in any gear except high gear and also operative to disengage" 50 and the; motor, the-connection with the atmosphererbeing: controlled by a :poweroperatedthreeway valve: operable to-control the gaseouspres surevw-ithin; the motor in its operation of controlling: the engagement 1 of the clutch; I

A further object of my invention is't'o provide aa-pressure balanced' valve" mechanism adapted-i be included as part of the mechanism for operating the friction clutch of an automotive ve ter valve' being power operated.

automotive'vehicle, a pressure balancedthree-way valv -mechanism operative in part-by a pressure" differential operated motor which is operative toeff'ect aaclutch engaging operation of the valve mechanism when the intake manifold'vacuumof' theengine' of the vehicle is suddenly clecreased;-

The-above and other objects and-features of theinventionlwill-appear more fully hereinafterfrom-a: consideration of thefollowing description taken in; consideration with the accompanying drawings wherein one embodiment/of theinvention is illustrated by way of example.

Figure 1- is a; diagrammatic view disclosing the" clutch control mechanism of my invention;

Figure 2 is a' longitudinal viewof" the threepart' three-waybleed valve me'chanismconstitilting the-principal feature of my invention; and- Figure 3 'isa sectional view disclosing details ofthe poweroperated three-way valve-oi myinven vide a clutch control mechanism adapted to be tion;

Describing now that embodiment of my invention disclosed in the several figures of the drawlngs the principal elements thereof consist of a single acting vacuum motor In comprising a casing I2 and a power element such as a piston, not shown, which is connected to a friction clutch, not shown, of a conventional design, that is, one including driving and driven elements. One end of the casing of the motor, a portion of the body thereof and the power element together outline a control chamber, the gaseous pressure within said chamber being controlled to control-the operation of the motor. The force transmitting means interconnecting the power element of the motor with the clutch preferably includes a flexible cable I4 connected to a crank l6 and said crank is fixedly connected to a shaft l6 which is connected to the clutch. A foot operated clutch pedal 28, contactable with a flange 2| extending from the crank I6, is also preferably included in the clutch operating mechanism.

One end of the motor 10, that is, the end of the same constituting a part of the aforementioned power compartment of the motor, is connected by a conduit 22 to a compartment 24 of a power operated three-way valve unit indicated as a whole by the reference numeral 26 and disclosed in detail in Figure 3. A compartment ll of said three-way valve unit 26 is connected, by

a conduit I3, with a port of a power operated three-part three-way bleed control valve unit indicated as a whole in Figures 1 and 2 by the reference numeral l5; and the aforementioned compartment 24 is connected, by a conduit IT, with a conduit l9 which conduit interconnects the air bleed valve I5 with a vacuum tank 9, said tank being connected, by a conduit 1, with the intake manifold 2| of the internal combustion engine 23 of the vehicle.

Describing now the details of the power operated three-way bleed valve l5, the casing 28 of said valve, constituting one of the three parts thereof, is provided with ports 38 and 3| venting the interior of the valve to the atmosphere; and said casing is also provided with a port 32 adapted to be connected with the vacuum tank 9 by means of a conduit 38. As is disclosed in Figure l the latter conduit is connected to the conduit 18. As is disclosed in Figure 2 the base of each of the ports 25, 38, 3|, and 32 is connected with an annular recess within the valve casing. The vacuum connection to the port 32 is controlled by a power operated vacuum cutin valve 33; and the power means for operating the latter valve includes a. solenoid 34 and a spring 35 the valve being biased to its closed position'by the spring and opened by the solenoid when the latter is energized.

The valve casing is bored to receive a sleeve 36 constituting a second part of the three-part bleed valve said sleeve being provided with ports 31, 38, and 33 adapted to register respectively, with the aforementioned recesses registering with the valve ports 38, 25, and 32. The sleeve 36 is actuated by the power element 46 of a pressure differential operated vacuum suspended motor 4|; and one of the two parts of the casing of said motor is fixedly secured to the valve casing 28. A. spring 42 within the motor 4| serves to move the power element into contact with stop 53" secured to the outer section of the motor 4|; and an adjustable bleed valve 43 serves to control the flow of air through a duct 44 said duct interconnecting chambers 45 and 46 of said motor. A conduit 41 serves to interconnect the motor chamber 46 with the vacuum conduit [9. Completing the description of the bleed valve l5 the p'osed between one end of the sleeve 36 and one .end of, the valve member 48, serves to bias the latter member to a position whereby the port 38 registers with the recess 58.

Describing now the power means for actuating the valve member 48 there is provided a two motored pressure differential operated motor unit 52 comprising casing members 53 and 54 having secured between them power elements 55 and 56. The motor casing member 54 is secured to the valve casing 28 thereby mounting the power unit 52 in position to actuate the valve member 48. A central chamber 55' of the unit 52 is vented to the atmosphere. via ports 56',and compartments 51 and 5B of said unit are connected respectively to an engine driven water pump 59, Figure l, and thevalve port 25, via a conduit 68 anda duct'6l in thebody of the valve casing 28 the duct 6| being disclosed in dotted lines in Figure 2. A leaf spring 65, the tension of whichmay be adjusted by a set screw 63, serves to bias the power elements 55 and 56 to the left, Figure 2. A pin 64, interconnecting the power elements 55 and '56, abuts one end of the valve member 48 the latter being moved into contact with said pin by the spring5l. Y 7

There is provided, by the unit 52, power means for actuating the valve member 48 to provide a pressure balanced three-way bleed valve. The

.force exerted by the pressure differential operated power elements 55 and 56 operate in one direction, that is, to the right, Figure 2, to balance the force exerted by the spring 5| in the opposite direction.

Completing the description of the clutch control mechanism constituting my invention the accelerator 66 of the vehicle is connected to a throttle operating crank 61 by the several links and bell crank levers disclosed in Figure 1; and as will appear from the description to follow one feature of my invention lies in the provision of a lost motion connection 68 in this throttle to accelerator connection.

Describing now the electrical control mechanism of my invention, as is disclosed in Figure 1 the solenoid 34, which together with the spring 35 operates the vacuum cutin valve 33, is controlled by a grounded shift rail operated switch 18 and by a grounded vehicle speed responsive governor operated switch 12 which is electrically connected in parallel with the switch 13. The latterswitch is biased to its closed position by a spring H1 and is opened by the transmission, preferably-the second and high gear shift rail thereof, when the transmission is established in its high gear setting. The armature 13' of a solenoid 14 is operative to actuate a valve member 76 of the three-way valve 26 said armature being controlled by the aforementioned grounded switches 18 and T2 and by an accelerator operated breaker switch 13. As is disclosed in Figure- 1 the latter switch is electrically connected in series with the solenoid I4 and the switches 18 and 12.. The construction of the switch 13 and its connectionwiththe accelerator is such that the same is closed when the accelerator is released and opened just prior to taking up all of the lost motion of'the connection 6t. is disclosed in Figure 1 the solenoids M :and H are electrically connected to the grounded loattery "34' providinga source of electrical energy for the electrical controls of :my invention,

Describing now the complete operation of the mechanism constituting my invention and incidentally completing the description of parts thereof not heretofore described, when the .accelerator =36 is released to close the throttle {of the internal combustion engine :23, the intake manifold ll of said engine is partially evacuated to in turn evacuate the vacuum :9. There is thus provided a source of vacuum for energizing the motor IE to disengage the nic ti'on'clutch of the vehicle; and this operation is effected with the release of'the accelerator to close the switch 13, and either a closingkof the transmission controlled switch T0 or a slowing down of the vehicle below governor speed to close the switch 12, either of said operations effecting an energization of the solenoid I! to open the Valve 16. the parts of the mechanism are so constructed and arranged that the bleed valve and the means for operating the same assume, at this time, the relative positions disclosed inFigure-2.

Explaining the latter operation when the valve 1 6 is opened as .a result of the energization :of the solenoid 14 the motor H! is energized to disengage the clutch; and at the same time the solenoid 34 is energized to open the vacuum cutin'valve 33 thereby connecting :the valve port 32 with the source of vacuum the latter operation resulting in an energization of the motor 52 to move the valve member 48 to the right to its lapped position, that is, the position disclosed The several forces acting upon the in Figure 2. valve member 48 to effect this lapping operation are described in detail hereinafter.

To initiate a clutch engaging operation Of the power means of my invention, that is, efleet the first sta e of clutch engaging operation of the r motor H], the driver depresses the accelerator to open the switch 13 it being remembered that.

the throttle is not opened during this operation; and said operation effects a de-energ-ization of the .solenoid 14 thereby permitting a spring 15 to .close the valve 16, that is, connect the control compartment of the motor H! with the port of the bleed valve 15 via the conduits l3 and 22. A continued depression of the accelerator serves to open the throttle and this operation serves, by virtue of the increase in pressure exerted by the fluid in the compartment 51', to again move the valve member 48 to the right thereby venting the compartment 58 to the atmosphere. Assuming that the driver then momentarily arrests the throttle opening movement of the accelerator the valve member 48 will then be moved to the left to again lap the valve this operation being effected by the reduction of the pressure acting to move the diaphragm 56 to the right, and the resultant operation of the spring 65 in its operation of biasing the valve member 4.8 to the left.

As to this valve lapping first stage operation an important feature of my invention lies in the construction, arrangement and adjustment of the parts of the valve (5, including the setting of the spring 65 and the force exerted by the Water within the compartment 51, to automatically eirecit this operation :of the valve; and

It is to be noted here that it is to be .remembered that during the opera- I tion of engaging the clutch, that is the operation :now being described, the gaseous pressure the compartment 58 oi the unit 52 and the gaseous pressure within the control compartment of the motor H] are the same at all times. -'The parts of the mechanism are preferably so constructed and arranged and so operative that the first stage of the clutch engaging operation, that is, movement of the driving clutch plate, is terminated just prior to the contacting of the clutch plates; and the valve 48 is automatically "lapped when this occurs.

Now to effect the all important controlled engagement of the clutch plates, that is, to effect the second stage clutch engaging operation of the power means of my invention, the driver continues the depression of the accelerator thereby 'eifecting an opening of the throttle to speed up the engine; and this operation results in an increase' in the .force exerted by the engine driven water pump 59 witha resultant increase in the pressure exerted by the water within the compartment}? of the motor 52; and this results in a movement of the valve member #8 to the right toagain vent the motor H1 and the valve compartment 58 to the atmosphere. This results in a reduction of the d'iiferential of pressures acting upon the power element of the motor m with a resultant loading of the clutch plates by the expanding ope-ration of the clutch springs. Thenwhen the gaseous pressure with in the compartment 58 is increased sufiiciently' to make the force exerted by the power element 56 plus the force exerted by the power element 55 equal to the force exerted by the spring 65, the valve 18 is again lapped. The power elemen-ts 55 and 56 and the spring of the motor unit 52 constitute three separate sources of ene gy serving to operate the valve member 48.

It is apparent therefore that there is provided, by the three-part three-way bleed control valve Ij'5 of my invention, means for efiect'ing a clutch plate loading which is directly proportional to the speed of the engine and this is exactly the result desired for the clutch plate loading should increase proportionately with the increase in engine torque. It is to be particularly noted that in the inechanismof my invention the summation U by the pump 59 increases the load of the power element 56 decreases, the force exerted by the spring 65 remaining a constant; for with an increase in the former load the valve 48 is pushed to the right, Figure 2, to vent the compartment 58 to the atmosphere; and when this occurs the d-ifierential of pressures acting .on the power element .56 is lowered. It follows therefore that when the driver wishes to increase the clutch plate loading said operation maybe effected mere- 1y by depressing the accelerator to increase the speed of the engine; for this operation resultsin a proportionately greater venerg-isation of the water pump 59 with a resulting expansion of the clutch springs to increase the-clutch plate loading.

, forces maintaining said valve lapped will be unalan d r sume in a movemen of the valv 48 to the left, Figure 2, to uncover the port and reconnect the motor l with the source of vacuum, that is the tank 9, said tank insuring a source of vacuum at all times during the operation of the clutch control mechanism of my invention. This operation of the valve IE will, of course, through the resultant increase in ener-' gization of the motor Hi, result in a lessening of the then existing clutch plate load, that is the load causing the engine to labor.

Now the vacuum connection with the valve port 32, Figure 2, is controlled by the vacuum cutin valve 33 the operation of which, by virtue of the electrical means disclosed in Figure 1, is controlled in part by the vehicle speed responsive governor, not shown. Below governor speed, and with the accelerator released to close the switch 13, the governor operated switch 12 is closed to energize the solenoid 14 to open the valve 33 accordingly it follows that the above described what may be termed recovery operation of the clutch control operation is only possible when the vehicle is traveling below governor speed; but with normal driving the engine torque is relatively high when the vehicle is traveling at a fairly high speed, that is above governor speed; accordingly, the above described recovery'of the mechanism is not needed at this time.

The most important feature of my invention lies in the provision of the pressure differential operated vacuum suspended motor 4|; forwith the inclusion of this motor in the mechanism there is provided power means for'efiecting the desired engagement of the clutch when the speed of the engine is suddenly increased. Explaining the difllculty to be overcome, and assuming for the moment that the mechanism does not include the motor 4|, should the driver suddenly increase the engine speed by say tramping hard upon the accelerator it would be necessary at this time to effect a corresponding substantial increase in the clutch plate loading; for otherwise the clutch would slip and the desired acceleration of the vehicle would not be obtained. With the motor 4| omitted from the mechanism of Figure 2 this is quick opening of the throttle would not result in a concurrent proportional increase in the clutch plate loading; this for the reason that due to frictional resistance to the movement of the air in the several conduits, the factor of inertia,

and other factors, there would be a lag in the right-ward movement of the valve member 46. But with the motor 4| included in the mechanism this relatively high factor of acceleration of engine speed immediately results in a substantial increase in the gaseous pressure within the compartment 46 of said motor. For it is to be remembered that the latter compartment is directly connected to the intake manifold 2| of the engine and to increase the engine speed there results a substantial decrease in the vacuum of the intake manifold, that is, substantial increase in the gaseous pressure within said manifold. Now there is very little resistance to flow of air from the manifold to the motor compartment 46 accordingly the substantial increase in gaseous pressure within the manifold 2| is immediately followed by a corresponding increase in the gaseous pressure within the motor compartment 46.

Explaining the operation of the motor 4|- it is to be noted that normally the gaseous pressure within the motor compartment 45 is equal to the pressure within the compartment 46 of the motor and that when the pressure within the latter when the throttle valve is opened wide 50 compartment is suddenly increased as explained above, there results a movement of the diaphragm 46 to the left, Figure 2; for said diaphragm is then subjected to a differential of pressures inasmuch as the bleed valve 43 operates to retard the flow of air from the compartment 46 to the compartment 45. The leftward movement of the diaphragm 40 results in a leftward movement of the valve sleeve 36 to uncover the port 38 and connect the same with the recess 50 in the valve member 48.

It follows therefore that with the mechanism of'my invention when the driver suddenly opens the throttle the bleed valve I5 is immediately operated by'the motor 4| to substantially increase the clutch plate loading exerted by the clutch springs. However, with a normal operation of the vehicle the motor 4| does not come into play the control being effected entirely by the motor unit 52.

There is thus provided a simple and compact clutch control mechanism the clutch being automatically disengaged when the accelerator is released to close the switch 13 and either the speed of the car is reduced below a certain factor to operate the governor operated switch 12 or the transmission is operating in any setting except high gear said setting resulting in a closing of the switch 10. The clutch is subsequently reengaged in two stages when the accelerator is depressed'to open the throttle the clutch loading during said engagement being proportional to the engine speed; and with the mechanism of my invention the clutch is automatically disengaged to terminate an undesired laboring of the engine; furthermore, with the mechanism of my invention the clutch is quickly engaged, to prevent "a slipping clutch action, when the driver suddenly opens the engine throttle.

Although only one embodiment of the invention has been illustrated and described, various changes in the form and relative arrangements of the parts may be made to suit requirements.

I claim:

1. In an automotive vehicle provided with an accelerator, a friction clutch and an internal combustion engine including an intake manifold; power means for operating the clutch including a pressure differential operated motor, valve means for controlling the operation of said motor including a three-way valve operable to effect a clutch disengaging operation of the motor and initiate a controlled clutch engaging operation of said motor, a three-part three-way bleed valve operable to control the flow of air into and from the motor via the three-way valve, a fluid transmitting connection interconnecting the manifold and three-way valve, a fluid transmitting connection interconnecting the three-way valve and bleed valve, a fluid transmitting connection interconnecting the three-way valve with the motor, and means for controllingthe valve means comprising accelerator operated means for controlling the three-way valve, and power means, comprising water pressure operated means for operating one part of the bleed valve and a pressure differential operated motor for operating another part of the bleed valve, the water pressure operated means being operative in accordance with the speed of the engine which is in turn controlled in part by an operation of the accelerator.

2. In an automotive vehicle provided with an accelerator, a throttle, force transmitting means, including a lost motion connection, interconnecting' the accelerator and throttle, a friction clutch, and an internal combustion engine including an intake manifold; power means for operating the clutch including a pressure differential operated motor, valve means for controlling the operation of said motor including a three-way valve and a three-way bleed valve operable to control the flow of air into and from the motor via the three-way valve said operation being efiected during a second stage of clutch engaging operation of the motor, a fluid transmitting connection interconnecting the manifold and three-way valve, a fluid transmitting connection interconnecting the three-Way valve and bleed valve, a fluid transmitting connection interconnecting the three-way valve with the motor, fluid transmitting connections interconnecting the bleed valve with the manifold, and means for controlling the valve means to effect a stage clutch engaging operation of the motor including an accelerator operated switch constituting part of the means for controlling the three-way valve, and power means, comprising a water pressure operated means, for operating the bleed valve, the water pressure operated means being operative in accordance with the speed of the engine which is in turn controlled in part by an operation of the accelerator, and the accelerator operated switch being operated, to initiate a first stage of clutch engaging operation of the motor, before the throttle is operated, said operation of the switch being made possible by virtue of the presence of the aforementioned lost motion connection in the force transmitting means interconnecting the throttle and accelerator.

3. In an automotive vehicle provided with an accelerator, a water motor, a friction clutch, an internal combustion engine including an intake manifold, an engine driven pump, and fluid transmitting means interconnecting the pump and motor; power means for operating the clutch including a vacuum motor, valve means for controlling the operation of the vacuum motor including a three-way valve operable to efiect a clutch disengaging operation of the vacuum motor and initiate a controlled clutch engaging operation of said motor, a bleed valve operable to control the flow of air into and from the vacuum motor via the three-way valve, a fluid transmitting connection interconnecting the manifold and three-way valve, a fluid transmitting connection interconnecting the three-way valve and bleed valve, a fluid transmitting connection interconnecting the three-way valve with the vacuum motor, and means for controlling the valve means comprising accelerator operated means for controlling the three-way valve, and power means for operating the bleed valve including the aforementioned water motor, a Vacuum motor, and a spring, the sum of the forces exerted by the two latter motors opposing the force exerted by the spring.

4. In an automotive vehicle provided with an accelerator, a water motor, a friction clutch, an internal combustion engine including an intake manifold, an engine driven pump, and fluid transmitting means interconnecting the pump and motor; power means for operating the clutch including a vacuum motor, valve means for controlling the operation of the latter motor including a three-way valve operable to effect a clutch disengaging operation of said motor and initiate a controlled clutch engaging operation of said motor, a bleed valve operable to control the flow of air into and from the vacuum motor via the three-way valve, a fluid transmitting connection interconnecting the manifold and three-way valve, a ,fluid transmitting connection interconnecting the three-way valve and bleed valve, a fluid transmitting connection interconnecting the three-way valve with the vacuum motor, and means for controlling the valve means comprising accelerator operated means for controlling the three-way valve, and power means for operating the bleed valve including the aforementioned water motor which is operable in accordance with the speed of the engine, a vacuum mo tor and a spring, the sum of the forces exerted by the two latter motors opposing the force exerted by the spring; together with another vacuum motor operable, when the vacuum within the same is suddenly and substantially reduced, to operate the bleed valve to effect a clutch engaging operation of the clutch operating vacuum motor.

EDWIN E. PRATHER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,087,305 Schmidtt et a1. July 20, 1937 2,111,322 Johnson Mar. 15, 1938 2,156,136 Watts Apr. 25, 1939 2,167,118 Lanser July 25, 1939 2,279,732 Brewer Apr. 14, 1942 2,296,282 Hruska Sept. 22, 1942 

